obis_mpa_belgium.Rmd

---
title: "obis_mpa_belgium"
output: github_document
---

```{r setup, include=FALSE, message = FALSE}
knitr::opts_chunk$set(echo = TRUE)
library(sf)
library(dplyr)
library(robis)
source("R-code/wdpar-package.R")

# robis::occurrence() expect filtering polygons in a well-known-text represerntation (aka WKT)
extract_polygon_geometry <- function(polygon) {
  polygon %>%
    sf::st_geometry() %>%
    sf::st_as_text()
}

```

## Global WDPA dataset flitered to Belgium

```{r wpda}
x <- sf::read_sf("~/data/WDPA_WDOECM_Apr2021_Public_marine.gpkg") %>%
  dplyr::filter(ISO3 %in% "BEL")
```

## Extract occurence data from OBIS

```{r obis}

# gets the occurrence data for a single multipolygon (one row of WDPA table)
get_one_mpa <- function(x, key){
   robis::occurrence(geometry = sf::st_as_text(sf::st_convex_hull(sf::st_geometry(x))))
}

bel_spoc <- x %>%
  dplyr::rowwise() %>%
  dplyr::group_map(get_one_mpa,
                   .keep = TRUE) %>%
  dplyr::bind_rows()
   
```